The present invention relates generally to ship repairing and pertains particularly to cofferdams for permitting in the water or dockside repair of ocean going vessels.
Many water borne cargo vessels, such as sea going ships and the like, have openings in the hull below water line for communicating with the water. Such openings are for many purposes including drawing of water from the ocean for cooling and the like and for expelling water and other waste material into the ocean. Such openings are typically connected by conduits and the like to pumps and other equipment within the engine room and other compartments of the vessel. It is sometimes necessary to replace or repair some of the plumbing in and around such openings and leading to such openings. It is also frequently necessary to add plumbing to the ship which communicates to the outside of the hull, in which case it is necessary to cut a hole in the hull and mount suitable conduit means therein.
It is also frequently necessary to repair holes in the hull below the water line. These repairs and reconstructions can be readily accomplished in dry dock. However, dry docks are frequently not available or are available only after a long wait.
It has been known, for example, to close openings in a ship's hull by means of mattresses, sheets of plywood, and the like for purposes of permitting replacement of plumbing inside the ship and the like. However, such approach can be dangerous and is highly unsatisfactory in most instances. Such approach is also unsatisfactory where it is necessary to repair or replace grill work or to do cutting and welding in and around the opening in the hull.
Accordingly, it is desirable that some means be available for permitting dock side repair of hull openings and the like of sea going vessels.